Filter card



y 1942- c. G. PETERSEN 2,282,301

FILTER CARD Filed Oct. 3, 1939- 61 61 1 85:) sen Patented May 5, 1942 UNITED STATES PATENT OFFICE FILTER CARD Carl G. Petersen, Bismarck, N. Dak.

Application October 3, 1939, Serial No. 297,751

2 Claims.

This invention relates to improvements in filter devices and pertains particularly to an improved filter card such as is employed for determining the presence of or separatingmilk slime and dirt in liquids.

In the process of determining the quantity'of dirt or foreign matter in milk and other liquids, the practice is to force a predetermined quantity of such liquid through a filtering medium of standard form and determining from the quantity of foreign matter or dirt accumulating upon the filtering material whether or not such milk is fit for human consumption. At the present time, these filtering bodies comprise a sheet of filtering material of suitable character which is fixed to an apertured card over the aperture or between a pair of apertured cards in position to cover such aperture and such card is placed in a suitable device by means of which the milk or other liquid can be forced through the filter which the card holds.

The present invention has for its primary object to provide a novel and improved type of filter card wherein there is employed a single card body which is divided or folded transversely to form two sections, each of which sections has an aperture therethrough, the apertures being brought into alinement when the two sections are folded together and novel means is employed by which the two sections can be secured together after a sheet of filtering material has been placed therebetween to be interposed between and overlie the registering apertures. With this form of filter card, the card bodies may be cut from a single sheet of material previously printed with suitable data and assembled as needed, thereby effecting a material saving in the cost of producing such cards as no gluing or sealing steps are required to secure the filtering sheet to the card and it is not required to bring together two independent bodies of any form which must be held in place, the assembling of the card merely comprising folding the same so as to bring into overlapping relation the two parts between which the filter sheet is located,

The invention will be best understood from a consideration of the following detailed description taken in connection with the accompanying drawing forming part of this specification, with the understanding, however, that the invention is not to be confined to any strict conformity with the showing of the drawing but may be changed or modified so long as such changes or modifications mark no material departure from the salient features of the invention as expressed in the appended claims.

In the drawing:

, Fig. 1 is a view in perspective of the filter card embodying the present invention.

Fig. 2 is a perspective View showing the card opened and the filter sheet removed.

' Fig. 3-is a perspective View of the filter sheet.

Referring now more particularly to the drawing, the numera1 I generally designates the body of the card or sheet from which the present filter card is formed. This body comprises a sheet of cardboard of suitable weight and of suitable length and width, which is folded transversely along the line 2 so as to form a major portion 3 and a smaller or minor portion 4. The minor portion has a width materially less than the major portion and the end edge thereof is cut to provide the centrally located securing tab or ear 5 while the major portion is provided with the centrally disposed transversely directed slit 6 in which the tongue 5 is adapted to engage.

Between the slit 5 and the fold line 2, the major portion 3 of the card is provided with a circular aperture l and the minor portion 4 is provided with a correspondingly formed aperture 8. These apertures are so disposed that when the two portions are brought into side by side relation in the manner shown in Fig. 1, the apertures l and 8 will be in registry. These two portions are secured in this relation by extending the tab 5 through the slit 6.

In assembling the filter card or unit, there is disposed between the portions 3 and 4 prior to folding them together, a sheet 9 of filter material of the character commonly employed in devices of the character disclosed. When the two portions of the card are connected together by the tab 5, this sheet of material, after being centered will be retained in place between the openings or apertures l and 8, as shown, and thus when the card is placed in the pumping apparatus in association with which it is used, the filter sheet 9 will be held firmly in position to have milk or other fluid forced therethrough in the usual well known manner.

The portion 3 of the card lying upon the slide of the slit 6 opposite from the aperture 1 may have printed matter of a suitable character placed thereon such as a statement to the effect that the sediment showing here on the card has been derived from a ounce sample taken from the milk submitted for test by a producer and that the milk has been rated as indicated by a checkmark which is placed on the card at any one of the four positions which are marked Clean, Dirty, Fairly Clean and Very Dirty. These markings are shown upon the card illustrated and the card is also provided with a suitable line H] for marking the name of the producer of the sample tested and the date submitted.

From the foregoing, it will be readily apparent that the filter cards or analytical devices herein disclosed may be economically prepared in view of the'fact that they may be out at one operation from a single piece of material and when they are to be put in use, it is merely necessary to fold the minor portion of the card against the major portion as previously stated,- after placing between the portions the sheet 9 of filter material.

quickly prepared for use at the place where and- The devices may thus'be sheet into a major .and a minor portion, said minor portion being designed to be folded along said line against the major portion, the said portions having apertures which are brought into registry when the portions are disposed in side by side relation, said minor portion having a flap extending in the plane thereof from one edge and the major portion having a transverse slit adapted to receive said flap for maintaining the minor portion pressed against a side of the major portion, and a sheet of filter material disposed between said portions over and between said apertures and held in position solely by its compression between the two portions.

2. As an article of manufacture for use in the formation of a filter card, an elongated sheet of cardboard having a transverse fold line at one side of the transverse center whereby the sheet isdivided into a major and a minor portion, said minor portion having an end edge flap extending in the plane of the minor portion and said major portion having a slit disposed across the longitudinal center into which said flap may be extended without folding to maintain said minor portion, when the sheet is folded alongsaid line against themajor portion, the said minorv and major portions having registering openings, the area of said major portion upon the side of said slit remote from the opening being relatively wide for the application of data.

. CARL G. PETERSEN. 

